Alloy.



HUGH s. 000231;, or cmavnmmnomo, Assr'cNoR TO THE GENERAL ALLOYS com'rAnY,

' A. CORPORATION or OHIO.

ALLOY.

Specification of Letters Patent. Patented Aug. 27, 1918- No Drawing. Original application filed February 23, 1918, Serial No. 218,791. Divided and this applcation filed April 17, 1918. Serial No. 229,173.

,To all whom it may concern:

Be it known that I, HUGH S. COOPER, citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Alloys, of whiclrthe following is a specification.

This invention relates to an alloy of relatively low-melting point having properties which make it superior to known high-speed steels used for cutting tools, and in this con- I nection reference may be had to my co-pending 'application for Letters Patent for an alloy. Ser. No. 218,791,filed February 23, 1918, of which thisapplication is a division. The present alloy comprises nickel or cobalt, zirconium, aluminum and silicon, or their equivalents, together with one or more metals of the chromium group, for example, tungsten, molybdenum, chromium or uranium. Thus, while the alloy described in my other application for Letters Patent has very desirable properties and characteristics. and forms the base of the present alloy, I have found that the addition of one or more of the metals of the chromium group improves the cutting efficiency of the alloy. For example, theaddition of about four per cent.

. tungsten to the quaternary alloy hereinbefore described will increase the cutting time of the tools before burning about one hundred per cent; the addition of seven per cent. tungsten will increase the time one hundred fifty per cent; the addition of twelve per cent. tungsten will increase the time about two hundred per cent. The limit apparently is reached with approximately twenty five per cent. tungsten, for beyond this the alloys become more brittle. Small amounts of chromium, molybdenum, or uranium may also be added-in some cases and proved beneficial.

The present alloy may be produced by any suitable method or process, but I prefer to make the alloy by reduction with powdered aluminum and by practising the method described in my co'pending application. Illustrating my general method, the desired proportion of nickel oxid black, and Brazilian zirkite carrying a minimum? of,about 80% zirconium oxid and about 15%? silica, is ground to 200 mesh, sifted, dried and thoroughly blended with the desired amount of 200 mesh aluminum. This mixture is transferred to a crucible or other suitable container lined with magnesia or alumina, and lighted with magnesium ribbon or otherwise. After the reaction when the slag has solidified the metal is tapped and transferred into a standardizing furnace and the desired amount. of metal of the chromium group is then dissolved into the molten alloy. More nickel may also be added if the alloy is too hard. After standardization the alloy is poured into molds made of carbon or other suitable material. The more desirable alloys comprise one to ten per cent. silicon,

one to twelve per cent. aluminum, one to twenty per cent. zirconium, one to twentyfive per cent. tungsten, and "the balance nickel or cobalt. The nickel or cobalt is always in preponderating amount.

In practice, to cut down the manufacturing cost it is desirable to make a composition showing a scleroscopic hardness of eighty to ninety, but a composition of this hardness does not possess sufiicient strength to be most eflicient for cutting tools. An alcent. of tungsten and twenty-four percent,

more nickel. However, by increasing the percentage of tungsten, the amount of nickel to be added maybe reduced to less than twenty-four per cent.

The following table shows several different compositions of value and utility Within the range and scope of my invention:

Aluminum, ap.prox. 7 .92 7.70 7.48

Silicon, approx. 3.80 3.50 3.40

Zirconium, approx 6.48 6.30 6.12

Nickel,"approx 7 8.00 7?.50 71.00

Tungsten, ap'prox. 4.00

However, I do not limit myself to the exact one-per cent. of each of the other metals or 7 their equivalents.

exceed twenty-five per cent. of the com position.

3. An alloy, comprising nickel, zirconium, aluminum, silicon, and a metal of the chromium group, in which the amount of nickel is greatest, and the amount of zirconium, and aluminum and silicon together is greater than the metal of the chromium group.

4. An alloy comprising nickel, zirconium, aluminum, silicon and tungsten, in which the proportion of nickel is greater than all the other metals combined, and the zirconium is less then the aluminum and silicon together, and the tungsten not in excess of twenty-live per cent. the Whole.

5. An alloy, comprising a metal in the iron group, one to twenty-live per cen age of nickel, relatively lesser percentages of zirconium and aluminum, and a. small amount of silicon, together With a. small percentoge of a metal belonging to the chromium" group of metals.

7. An alloy, comprising one to ten per cent'silicon, one to twelve per cent. aluminum, one to twenty per cent zirconium, and one to twenty-five per cent. tungsten, the balance being a. metal of the iron group.

8. An alloy, comprising seventy to eighty per cent. nickel, four to twelve per cent. tungsten, seven to eight per cent. aluminum, six to seven per cent. zirconium, and three to four per cent. silicon.

Signed at Cleveland, in the county of Guyehogu, and State of Ohio, this 2nd day of April, 1918.

nncn s. coornn.

Bil 

